some h55f and split case tech (6 Viewers)

[AlbertoSD]

To add some additional images to this thread, below is a photo of 3 of the input shafts that Toyota offered for the H55f transmission:

Left: F, 2F, 3F, H, 2H, 12HT type H55 input shaft.
Middle: HZ type H55 input shaft
Right: B, 2B, 3B, 13BT type H55 input shaft

I've included what I've found through reading on the forum. The photo above also shows the late iteration of the H55 input shafts with the bigger bearing and the late type front bearing retainer. Please correct me if I have listed them wrong.

For reference:

HZ type H55 input shaft part number:

Late 3B type H55 input shaft part number:

Hope this helps,

-Alberto

 

[FJ40Jim]

For the record, while we were swapping out Alberto's 3B to HZ input shaft, we realized (a little too late) that it is not necessary to pull the mainshaft rear bearing if the only work being done is swapping the input gear. It is only necessary to pull F & R countershaft bearing, then pull input bearing & input gear. Sorry Alberto!

 

[FJ40Jim]

Some pics of interchangeable & non interchangeable H42 & H55 parts.

Here is a 1987 H42 and 1985 H55 transmission housing. Both housings are fully drilled & tapped for 5th gear, so either housing can be used with 4 or 5 gears. IDK if early (short) H42 will look like this.

We are using this 4 speed housing with 5speed guts because the later housing has the bigger input bearing bore which works with the new, bigger H55 input gear. Plus rebuilding the 5spd anyway, plus the H42 has 287K miles & is totally shot, plus the H42 case is very clean on the outside vs the rusted ass canadian BJ70 case.

Another view showing the top covers are identical.

On to the main shafts. Very close to interchangeable. They start off as the same blank, but the H55 shaft has one more machining step done to it; Splines are cut for 5th gear. If there were no more H55 shafts on the planet, a good machine shop could cut the splines on the H42 shaft, making it into an H55 shaft. And yes, for some reason the H42 tranny & transfer were full of red Dexron.

The countershaft are completely different because of ratios and the H42's lack of 5th gear tail extension.

The service parts are all the same in a given year: bearings, seals, syncros, etc.
The 1-2 syncro/reverse gear is also the same, along with reverse idler gear.
Sorry, no pics of that.

HTH.

 

[cruisermatt]

Very cool and good info. Thanks Jim.

 

[FJ40Jim]

The 4 gear section of the h55 rebuilt into the H42 housing w/ H42 reverse gear &shifter.

 

[cruisermatt]

@FJ40Jim I see the Permatex Engine Assembly Lube in the background of the photo, assuming you would recommend this as a transmission assembly lube?

 

[Spike Strip]

AKA, Red Lube of Love.

 

[FJ40Jim]

Yes, good stringy oil that will hang around if this tranny doesn't get stabbed into my 60 for a few months.

 

[roma042987]

just to make a very small contribution to this great thread. Im in the process of rebuilding my 3rd split case this month and recently came across something I haven't came across before. Apparently there is a later model rear bearing retainer that actually takes a larger seal. Thanks Georg for the heads up and here is a photo of the part number.

 

[FJ40Jim]

While wheeling my recent "junkyard special" H55 & t-case this weekend, the t-case would occasionally kick out of 4WD under load. I noticed when assembling the t-case that when the FWD shifter was slid forward to it's detent there was very little engagement of the collar on the front shaft splines.
Mark A said he thought there was a TSB about this problem. Does anybody know what this TSB suggests as a fix? Perhaps an updated shift shaft or fork to move the collar forward?
My planned cheapskate fix for this is to partially weld up & re-grind the detent in the shift shaft to get the shift collar to move all the way forward to the limit of travel.

 

[Spike Strip]

TSB for transfercase detent springs (problems with H4 or L4 slipping out)

 

[Spike Strip]

TSB for transfercase detent springs (problems with H4 or L4 slipping out)

 

[FJ40Jim]

Thanks Spike! I'll try that first. If it still kicks out, it's because the slightly worn fork and slightly worn shift collar are not engaging quite far enough. Surgical intervention is required in that case.

 

[orangefj45]

Great info Spike!

There are a couple of versions of the shift collar as well. Just like the later rear extension housing, there's a later 2-4 shift collar that's only chamfered on one side. The other side is machined flat. I'm guessing that Toyota did this to save a little bit of cost since at least 2 steps in the machining process are eliminated.
I'll dig out a late collar today and will post pics.

Georg @ Valley Hybrids & Cruiser Brothers

 

[orangefj45]

Also, I keep new H55F main shafts and Tcase output shafts in stock if anybody needs one.

Georg @ Valley Hybrids & Cruiser Brothers

 

[orangefj45]

Ok. Found something today that I've never seen before ( and I've looked at a few of these ...... ).
I'm building an NV4500-split case combo for a customer right now. Doing a conversion on his LS powered FJ60.
The factory PTO gear in this Tcase doesn't have chamfered teeth. So if this was to be used, it'd be pretty tough to engage. Not sure what the thinking behind this is.

Anyways, here's a pic showing both styles.

Georg @ Valley Hybrids & Cruiser Brothers

 

[mdsims]

Maybe mine use, military, fire trucks or some other purpose-built cruisers got the non-chamfered gearset? I'd assume the full tooth width must be a bit stronger.

Where did the customer get the split case? Stock one in his rig?

 

[GLTHFJ60]

View attachment 1349501 Ok. Found something today that I've never seen before ( and I've looked at a few of these ...... ).
I'm building an NV4500-split case combo for a customer right now. Doing a conversion on his LS powered FJ60.
The factory PTO gear in this Tcase doesn't have chamfered teeth. So if this was to be used, it'd be pretty tough to engage. Not sure what the thinking behind this is.

Anyways, here's a pic showing both styles.

Georg @ Valley Hybrids & Cruiser Brothers

I feel like I've seen that before, but can't put my finger on it. Maybe Toyota saved some $$ om machining that gear because they knew it wouldn't be used?

 

[orangefj45]

And here's a pic of the non-chamfered slider I mentioned earlier in this thread. I've seen a few of these on later split cases, mostly 2006 and newer 70-series rigs. If you rebuild your Tcase and it has the non-chamfered version, then make sure you install it on the 2-4 rail with the non-chamfered portion facing the rear of the case or it'll be hard to shift into 4wd.
If you install it on the main shaft, it'll be really difficult to shift into whichever gear the non-chamfered side is facing.

Georg @ Valley Hybrids & Cruiser Brothers

 

[FJ40Jim]

On the non-chamfer PTO gear, the only Toyota PTO boxes I have seen were constant engagement type, i.e. they are always engaged in the t-case drive gear, with shifting of forward/reverse done inside the PTO box.

Single speed domestic PTO boxes will be the type that completely disengages from the drive gear, and then need the chamfer to slide the driven gear back into the drive gear.